Google Weather Integration for Home Assistant

A comprehensive Home Assistant integration that provides weather data from the Google Weather API with current conditions, forecasts, and alerts.

Features

• Complete Weather Data: Current conditions, daily forecast (up to 10 days), hourly forecast (up to 240 hours)
• Weather Alerts: Real-time weather warnings and alerts from authoritative agencies worldwide
• Comprehensive Sensors: 25+ observational sensors including temperature, wind, precipitation, snow, UV index, and more
• Binary Sensors: Day/night detection and weather alerts (when supported)
• Region-Friendly: Support for both Metric and Imperial unit systems
• Configurable Location: Set custom coordinates via config and options flow
• API Key Authentication: Simple setup using Google Maps API key
• HACS Compatible: Easy installation and updates

What You'll Get

Weather Entity

• Current Conditions: Temperature, feels-like, humidity, pressure, wind speed/direction, visibility, cloud cover, UV index, and more
• Daily Forecast: Up to 10 days with high/low temperatures, conditions, precipitation probability, and more
• Hourly Forecast: Up to 240 hours (10 days) of detailed hourly forecasts

Observational Sensors (25+ sensors)

Temperature:

• Current Temperature
• Feels Like Temperature
• Dew Point
• Heat Index
• Wind Chill

Wind:

• Wind Speed
• Wind Gust
• Wind Direction (full cardinal)
• Wind Cardinal (abbreviated: N, NE, E, etc.)
• Wind Degrees (0-360°)

Atmospheric:

• Humidity
• Pressure
• Visibility
• Cloud Cover
• UV Index

Precipitation & Snow:

• Precipitation Probability
• Precipitation Amount
• Snow Amount
• Snow Forecast (next 24h, requires hourly forecast)
• Thunderstorm Probability

24-Hour Historical:

• Temperature Change
• Max Temperature
• Min Temperature
• Total Precipitation
• Total Snow

Other:

• Weather Condition (text description)

Binary Sensors

The integration creates a "Binary Sensors" device linked to the weather device:

Always Available:

• Daytime: Indicates if it's currently daytime (based on sunrise/sunset)

Weather Alerts (only if your region supports alerts):

• Weather Alert: Any active weather alerts
• Severe Weather Alert: Extreme or severe alerts only
• Urgent Weather Alert: Immediate or expected urgency alerts

All alert sensors include detailed attributes with alert descriptions, instructions, severity levels, and more.

Alert Availability: The integration automatically detects if your location supports weather alerts during setup. If the API returns a 404 error, only the Daytime sensor is created. All weather data and forecasts continue to work normally. See Supported Regions for alert coverage details.

Prerequisites

1. Google Cloud Project: Create a project at Google Cloud Console
2. Google Weather API: Enable the Weather API in your project
3. API Key: Create a Google Maps API key in Google Cloud
4. Home Assistant: Version 2023.1 or later

Installation

Via HACS (Recommended)

1. Open HACS in Home Assistant
2. Click on "Integrations"
3. Click the three dots in the top right corner and select "Custom repositories"
4. Add this repository URL: https://github.com/safepay/ha_google_weather
5. Select "Integration" as the category
6. Click "Install"
7. Restart Home Assistant

Manual Installation

1. Download or clone this repository
2. Copy the custom_components/google_weather folder to your Home Assistant config/custom_components/ directory
3. Your directory structure should look like:

   config/
   └── custom_components/
       └── google_weather/
           ├── __init__.py
           ├── manifest.json
           ├── config_flow.py
           ├── coordinator.py
           ├── const.py
           ├── weather.py
           ├── sensor.py
           ├── binary_sensor.py
           ├── application_credentials.py
           ├── strings.json
           └── translations/
               └── en.json
   

4. Restart Home Assistant
5. The integration will appear in Settings → Devices & Services → Add Integration

Configuration

Step 1: Get Your Google Maps API Key

1. Go to Google Cloud Console
2. Select your project (or create a new one)
3. Navigate to "APIs & Services" → "Library"
4. Search for "Weather API" and click "Enable"
5. Go to "APIs & Services" → "Credentials"
6. Click "Create Credentials" → "API key"
7. Copy your Google Maps API key (you can add restrictions for better security)

💡 Tip: If you already have a Google Maps Platform API key, you can reuse it! Just make sure the Weather API is enabled for your project.

Step 2: Add the Integration

1. Go to Settings → Devices & Services
2. Click "+ Add Integration"
3. Search for "Google Weather"
4. Enter your Google Maps API key from Step 1
5. Configure your location:
   • Location: Entity ID prefix (default: "home") Examples: "home", "office", "weather_station"
   • Latitude: Location latitude (defaults to Home Assistant location)
   • Longitude: Location longitude (defaults to Home Assistant location)
   • Unit System: Choose METRIC or IMPERIAL
6. Choose forecast and alert options:
   • Include Daily Forecasts: Enable automatic fetching of daily forecasts (enabled by default)
   • Include Hourly Forecasts: Enable automatic fetching of hourly forecasts (enabled by default)
   • Include Weather Alerts: Enable automatic fetching of weather alerts (enabled by default)
   • Tip: Disable forecasts you don't need to save API calls. You can still access them manually via the weather.get_forecasts action.
7. Configure update intervals:
   • Set how often each enabled endpoint updates during day/night
   • Only enabled forecasts/alerts will show interval configuration
   • Defaults are optimized for the free tier (10,000 calls/month)

That's it! Your weather data will start flowing immediately.

Entity Naming

The integration creates simple, clean entity IDs and friendly names. Entities are organized into three separate devices linked via device hierarchy (via_device):

Example: Location = "home"

Device: "Home Weather" (Parent Device)

Weather Entity:

• weather.home_weather → Friendly name: "Home"

Device: "Home Observational Sensors" (Child Device)

Linked to parent device via via_device. Contains 25+ sensor entities:

• sensor.home_temperature → "Home Temperature"
• sensor.home_feels_like → "Home Feels Like Temperature"
• sensor.home_dew_point → "Home Dew Point"
• sensor.home_wind_speed → "Home Wind Speed"
• sensor.home_wind_cardinal → "Home Wind Cardinal"
• sensor.home_wind_degrees → "Home Wind Degrees"
• sensor.home_humidity → "Home Humidity"
• sensor.home_pressure → "Home Pressure"
• sensor.home_visibility → "Home Visibility"
• sensor.home_uv_index → "Home UV Index"
• sensor.home_snow_amount → "Home Snow Amount"
• sensor.home_snow_24h → "Home Snow (24h)"
• ...and 13+ more sensors

Device: "Home Binary Sensors" (Child Device)

Linked to parent device via via_device.

Always available:

• binary_sensor.home_is_daytime → "Home Daytime"

If region supports alerts:

• binary_sensor.home_weather_alert → "Home Weather Alert"
• binary_sensor.home_severe_weather_alert → "Home Severe Weather Alert"
• binary_sensor.home_urgent_weather_alert → "Home Urgent Weather Alert"

Note: The "Binary Sensors" device is always created with at least the Daytime sensor. Weather alert sensors are only added if your location supports alerts (see Supported Regions).

Smart Polling & API Optimization

Overview

The integration uses smart polling to optimize API usage and stay within Google's free tier limits. Google provides 10,000 free API calls per month, and this integration is designed to make efficient use of this limit.

Forecast & Alert Options

You can choose which optional forecasts and alerts to include during setup:

• Daily Forecasts: Always enabled - up to 10-day forecasts (not configurable, maximum available always fetched, number of days available is region-dependent)
• Hourly Forecasts: Optional - Enable/disable automatic fetching of up to 240-hour forecasts (maximum available always fetched, number of hours available is region-dependent)
• Weather Alerts: Optional - Enable/disable automatic fetching of weather alerts (checkbox always shown, but alert entities only created if supported in your region)

Benefits of disabling optional forecasts:

• Reduces API calls: Disabled endpoints are never fetched automatically, saving API calls
• Flexible API management: Only fetch what you actually use regularly

Example API savings (with defaults):

• Disabling hourly forecasts: Saves ~1,680 calls/month
• Disabling weather alerts: Saves ~2,400 calls/month
• Disabling both: Saves ~4,080 calls/month

Note: Daily forecasts are always enabled because they're the most commonly used forecast type and update less frequently than hourly forecasts, making them efficient in terms of API usage.

Manual Forecast Fetching

The integration includes a custom service for fetching forecasts on demand:

Service: google_weather.get_forecast

Parameters:

• entity_id: Your weather entity (e.g., weather.home)
• forecast_type: Either daily or hourly

Example service call:

service: google_weather.get_forecast
data:
  entity_id: weather.home
  forecast_type: hourly

This makes a single API call to fetch the requested forecast and returns the raw data from the Google Weather API.

Use cases:

• You have hourly forecasts disabled but want to fetch them on-demand via an automation
• You want to fetch a forecast only when you explicitly need it (e.g., via a dashboard button)
• You're using the free tier and want maximum control over API usage

How It Works

Instead of fetching all weather data at once, the integration checks each enabled API endpoint individually and only fetches when needed:

• Current Conditions: Always enabled - updates frequently (default: every 10 min during day, 30 min at night)
• Daily Forecast: Always enabled - updates less frequently as it changes slowly (default: every 30 min during day, 60 min at night)
• Hourly Forecast: Optional - moderate update frequency (default: every 20 min during day, 60 min at night)
• Weather Alerts: Optional - important but checked moderately (default: every 15 min during day, 30 min at night)

The coordinator runs every minute to check which enabled endpoints need updating, but only calls the Google API when an endpoint's interval has elapsed.

Default Configuration

The default settings are optimized to stay within the 10,000 free calls/month limit with a healthy buffer:

Endpoint	Daytime Interval	Nighttime Interval	Approx. Calls/Month
Current Conditions	10 minutes	30 minutes	~3,360
Daily Forecast	30 minutes	60 minutes	~1,200
Hourly Forecast	20 minutes	60 minutes	~1,680
Weather Alerts	15 minutes	30 minutes	~2,400

Total: ~8,640 calls/month (13.6% under the 10,000/month free tier limit, providing a comfortable buffer)

Configuring Update Intervals

During setup (Step 2 of configuration), you can customize update intervals for each endpoint:

1. Current Conditions - How often to fetch current weather (temperature, humidity, wind, etc.)
2. Daily Forecast - How often to update the 10-day forecast
3. Hourly Forecast - How often to update the 240-hour forecast
4. Weather Alerts - How often to check for new weather alerts

Each endpoint has separate settings for:

• Daytime interval: When you want more frequent updates (e.g., 06:00 - 22:00)
• Nighttime interval: When less frequent updates are acceptable (e.g., 22:00 - 06:00)

Nighttime Configuration

You can configure when "nighttime" begins and ends:

• Night Start: When to switch to nighttime intervals (default: 22:00 / 10 PM)
• Night End: When to switch back to daytime intervals (default: 06:00 / 6 AM)

This automatically reduces API calls during nighttime hours when weather changes less and you're less likely to check the weather.

Example Configurations

Power User (Maximum Updates)

• Current: 5 min day / 10 min night = ~7,200 calls/month
• Daily: 15 min day / 30 min night = ~2,400 calls/month
• Hourly: 10 min day / 20 min night = ~3,600 calls/month
• Alerts: 10 min day / 20 min night = ~3,600 calls/month
• Total: ~16,800 calls/month (requires paid plan)

Conservative (Minimal Updates)

• Current: 30 min day / 60 min night = ~1,200 calls/month
• Daily: 60 min day / 120 min night = ~600 calls/month
• Hourly: 30 min day / 90 min night = ~1,120 calls/month
• Alerts: 30 min day / 60 min night = ~1,200 calls/month
• Total: ~4,120 calls/month (well within free tier)

Alerts Priority (Emergency Notifications)

• Current: 30 min day / 60 min night = ~1,200 calls/month
• Daily: 60 min day / 120 min night = ~600 calls/month
• Hourly: 30 min day / 90 min night = ~1,120 calls/month
• Alerts: 10 min day / 15 min night = ~3,840 calls/month
• Total: ~6,760 calls/month (prioritizes alerts, within free tier)

Tips for Staying Within Free Tier

1. Use defaults: The default settings are optimized for the free tier
2. Increase nighttime intervals: You probably don't need updates every 5 minutes at 3 AM
3. Adjust by importance: Set longer intervals for daily forecasts (they change slowly)
4. Monitor usage: Check your Google Cloud Console for API usage
5. Consider your needs: Most users don't need sub-5-minute updates

Location Configuration

The location field serves as the entity ID prefix and friendly name:

• Location: Identifier used in entity IDs (default: "home")
• Coordinates: Default to your Home Assistant location but can be customized
• Friendly Names: Auto-generated from location using title case

Examples:

• Location: "home" → Entity IDs: weather.home, sensor.home_temperature
• Location: "office" → Entity IDs: weather.office, sensor.office_temperature
• Location: "gw_home" → Entity IDs: weather.gw_home, sensor.gw_home_temperature

Updating Configuration

You can update location coordinates, unit system, forecast options, and update intervals at any time:

1. Go to Settings → Devices & Services
2. Find the Google Weather integration
3. Click "Configure"
4. Update any of the following:
   • Location coordinates (latitude/longitude)
   • Unit system (Metric/Imperial)
   • Forecast and alert inclusion (enable/disable daily forecasts, hourly forecasts, weather alerts)
   • Update intervals for enabled endpoints (daytime and nighttime)
   • Nighttime schedule (start and end times)
5. Click "Submit"

The integration will automatically reload with the new settings. Changes to forecast options and update intervals take effect immediately.

Note: When you disable a forecast or alert option, the corresponding binary sensors will not be created on reload. Re-enabling them will restore the sensors.

Unit Systems

The integration supports both Metric and Imperial unit systems. Choose your preferred system during setup, and the Google Weather API will return data in those units.

Metric (Default for most regions)

• Temperature: Celsius (°C)
• Wind Speed: Kilometers per hour (km/h)
• Precipitation: Millimeters (mm)
• Visibility: Kilometers (km)
• Pressure: Millibars (mbar)

Imperial (US and some other regions)

• Temperature: Fahrenheit (°F)
• Wind Speed: Miles per hour (mph)
• Precipitation: Inches (in)
• Visibility: Miles (mi)
• Pressure: Millibars (mbar) Note: API does not convert pressure

API Behavior: The Google Weather API automatically converts most values based on your selected unit system. However, air pressure is always returned in millibars regardless of the unit system setting.

Usage Examples

Display Weather on Dashboard

type: weather-forecast
entity: weather.home
forecast_type: daily

Weather Warning Automation

automation:
  - alias: "Severe Weather Alert"
    trigger:
      - platform: state
        entity_id: binary_sensor.home_severe_weather_alert
        to: "on"
    action:
      - service: notify.mobile_app
        data:
          message: >
            {% set alerts = state_attr('binary_sensor.home_severe_weather_alert', 'alerts') %}
            {% for alert in alerts %}
            {{ alert.title }}: {{ alert.instruction }}
            {% endfor %}
          title: "⚠️ Severe Weather Alert"

UV Index Notification

automation:
  - alias: "High UV Index Alert"
    trigger:
      - platform: numeric_state
        entity_id: sensor.home_uv_index
        above: 7
    condition:
      - condition: time
        after: "09:00:00"
        before: "16:00:00"
    action:
      - service: notify.family
        data:
          message: "UV index is {{ states('sensor.home_uv_index') }}. Remember sunscreen!"

Temperature Trend

# Track temperature changes over 24 hours
sensor:
  - platform: template
    sensors:
      temperature_trend:
        friendly_name: "Temperature Trend"
        value_template: >
          {% set change = states('sensor.home_temp_change_24h') | float %}
          {% if change > 5 %}
            Rising significantly
          {% elif change > 0 %}
            Rising slightly
          {% elif change < -5 %}
            Falling significantly
          {% else %}
            Falling slightly
          {% endif %}

Weather Alert Attributes

The weather alert binary sensors include comprehensive attributes:

# Example attributes on binary_sensor.home_weather_alert
alert_count: 2
max_severity: "SEVERE"
data_source: "National Weather Service"
alerts:
  - alert_id: "urn:oid:..."
    title: "Flash Flood Warning"
    event_type: "FLASH_FLOOD"
    area: "Franklin County"
    severity: "SEVERE"
    certainty: "LIKELY"
    urgency: "IMMEDIATE"
    start_time: "2025-08-06T18:24:00Z"
    expiration_time: "2025-08-06T21:30:00Z"
    description: "Flash flooding in progress..."
    instruction: "Turn around, don't drown..."

Data Updates

The integration uses smart polling with configurable intervals for each endpoint:

• Current Conditions: Default 10 min (day) / 30 min (night) - real-time weather updates
• Daily Forecast: Default 30 min (day) / 60 min (night) - 10-day forecast
• Hourly Forecast: Default 20 min (day) / 60 min (night) - 240-hour forecast
• Weather Alerts: Default 15 min (day) / 30 min (night) - real-time alerts

The coordinator checks every minute to see if any endpoint needs updating, but only makes API calls when necessary. This provides responsive updates while staying within API limits.

Nighttime Mode: Automatically reduces update frequency during configured nighttime hours (default: 22:00 - 06:00).

Troubleshooting

"Missing credentials" error

• Ensure you've added Google Application Credentials in Settings → Application Credentials
• Verify your API key is correct and has the Weather API enabled
• Check that API key restrictions allow access from your Home Assistant instance

API errors

• Check that the Google Weather API is enabled in your Google Cloud Console
• Verify your Google Cloud project has billing enabled (Weather API requires billing)
• Check Home Assistant logs for detailed error messages: Settings → System → Logs

Entities not appearing

• Check that the integration loaded successfully in Settings → Devices & Services
• Verify the coordinator is fetching data (check logs)
• Try reloading the integration or restarting Home Assistant

Wrong units

• Check the unit system setting in the integration options
• Reload the integration after changing the unit system

No weather alert sensors (only Daytime sensor)

• If you only see the Daytime binary sensor, your region does not support weather alerts through the Google Weather API
• The integration automatically detects alert support on first setup - if the API returns a 404 error, only the Daytime sensor is created
• Check the integration logs for the message: "Weather alerts not supported for this location - only creating non-alert binary sensors"
• This is normal and expected for unsupported regions - the integration will continue to work perfectly with all weather data and forecasts
• Not all regions have weather alert support through Google's API (see Supported Regions for details)

No active weather alerts (sensors exist but show "off")

• Weather alerts depend on whether there are currently active alerts in your area
• Binary sensors will be in the "off" state when there are no active alerts
• This is normal - alerts only activate when severe weather is occurring or expected

Supported Regions

Weather Data (Current Conditions, Forecasts)

Available worldwide for any latitude/longitude coordinates.

Weather Alerts Coverage

Weather alerts are available in many countries, but coverage varies by region. The integration automatically detects whether your location supports alerts during initial setup.

How Alert Detection Works:

• On first setup, the integration checks if the Google Weather API supports alerts for your location
• If supported (HTTP 200): All binary sensors are created (Daytime + 3 alert sensors)
• If not supported (HTTP 404): Only the Daytime sensor is created - this prevents misleading empty alert sensors
• This detection happens once during initial setup and the result is cached

Alert Availability:

• Weather alert coverage varies significantly by country and region
• Some countries have full national coverage, while others have limited regional support
• The Google Weather API aggregates alerts from official government agencies worldwide
• See the Google Weather API documentation for specific coverage in your region

What Happens in Unsupported Regions: If alerts are not available for your location:

• You'll see a log message: "Weather alerts not supported for this location - only creating non-alert binary sensors"
• The "Binary Sensors" device is still created with the Daytime sensor
• The three weather alert binary sensors will NOT be created
• All other weather data and forecasts will work perfectly
• This is the expected behavior and prevents cluttering your UI with sensors that can never have data

API Limitations & Pricing

Free Tier

• 10,000 free API calls per month (total across all endpoints combined)
• No credit card required for free tier
• Default configuration uses ~8,640 calls/month (13.6% under the limit)

Smart Polling Benefits

• Each endpoint is polled independently at different intervals
• Nighttime mode automatically reduces API usage by 40-60%
• Cached data is returned when endpoints don't need updating
• Graceful fallback to cached data if API errors occur

Billing

• Weather API requires a Google Cloud project (billing info may be required)
• Free tier resets monthly
• Charges apply only if you exceed 10,000 calls/month total
• Current pricing: $6.00 per 1,000 calls after free tier

Recommendations

1. Start with defaults: Optimized for ~8,640 calls/month (13.6% under the 10,000 limit)
2. Monitor usage: Check Google Cloud Console → APIs & Services → Dashboard
3. Adjust as needed: Reduce intervals if approaching limits
4. Use nighttime mode: Significant savings with minimal impact
5. Set billing alerts: Get notified if approaching free tier limit

Forecast Data Limits

• Daily forecast: Up to 10 days
• Hourly forecast: Up to 240 hours (10 days)
• Current conditions: Real-time
• Weather alerts: Real-time from 50+ countries

Support

For issues and feature requests, please use the GitHub issue tracker.

License

MIT License - See LICENSE file for details

Credits

This integration uses the Google Weather API provided by Google Maps Platform.